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AVO FEASIBILITY STUDY FOR HYDROCARBON DETECTION IN NORTHWESTERN PART OF THE PATTANI BASIN, GULF OF THAILAND |
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| รหัสดีโอไอ | |
| Creator | Kumhang Punglusamee |
| Title | AVO FEASIBILITY STUDY FOR HYDROCARBON DETECTION IN NORTHWESTERN PART OF THE PATTANI BASIN, GULF OF THAILAND |
| Contributor | - |
| Publisher | Department of Geology, Chulalongkorn University |
| Publication Year | 2557 |
| Journal Title | Bulletin of Earth Sciences of Thailand (BEST) |
| Journal Vol. | 7 |
| Journal No. | 2-Jan |
| Page no. | 94-105 |
| Keyword | PattaniBasin,Rock Physics, AVO analysis |
| URL Website | https://www.bestjournal.org/ |
| Website title | Bulletin of Earth Sciences of Thailand |
| ISSN | 1906-280X |
| Abstract | The Pattani Basin is one ofthe prolific areas for hydrocarbon exploration within the Gulf of Thailand. The main reservoirs of the area are Lower to Middle Miocene sands associated with fluvial depositional systems. Detection and quantification of hydrocarbon zones is not always accurate only by using conventional seismic amplitudes. I applied rockphysics and AVO technique on one of the hydrocarbon fields of the northern PattaniBasin to understand AVO response for different fluids and for different reservoir thicknesses. According to rock physics analysis, Pimpedance alone cannot successfully differentiatewater-wet and gassaturated sands. However, used in conjunction with Poisson's ratio it can separate gas-saturated sands. Similarly, cross-plot of Lambda-Rho vs Mu-Rho can also separates gas-saturatedzones. AVOmodeling reveals that most of the gas sands are class-III sands. Some of the gas sands and water-wetsands deviate from general predicted trend. The possible reasons for these deviations are 1) thickness of sandsis belowtuning thickness 2) Shales with very low Poisson's ratio over sand reservoirs. According to wedge modeling results, gas sands below tuningthickness do not show typical class III response. Presence of very low Poisson's ratio shales above the sand reservoirs may affect AVO response as AVO depends upon contrast of Poisson's ratio. AVO attribute analysis indicates that scaled Poisson's ratio change is more suitable to detect gas sands within this area. The sands greater than tuning thickness can be detected more effectively by AVO attributes as compared to thin sands. Extracted horizon slices of scaled Poisson's ratio can provide usefulinformationfor promising exploration zones, if analyzed with structure contour maps. |
